To this end, an installation for treating containers by electron bombardment comprises a structure having pivotally mounted thereon an inlet starwheel and an outlet starwheel that are arranged respectively facing an inlet and an outlet of a shielded enclosure in which there are mounted a pivoting treatment starwheel and one or more electron emitters in the vicinity of the treatment starwheel. The starwheels are provided with gripper means for holding the containers so that the containers pass from one starwheel to another from the inlet towards the outlet.
In order to attenuate the energy of the X-rays emitted by the emitter and in order to prevent them from leaving the shielded enclosure, it is known to place shielded internal partitions inside the enclosure, which partitions are arranged as baffles towards the inlet and the outlet of the shielded enclosure. A “baffle” arrangement means an arrangement in which the internal partitions are arranged so as to prevent any direct path for X-rays from the emitter to the inlet or to the outlet. Thus, X-rays emitted by the emitter towards the containers are reflected against the walls of the shielded enclosure and the shielded internal partitions a sufficiently large number of times to ensure that they have lost most of their energy before reaching the inlet or the outlet of the shielded enclosure.
Installing internal partitions makes it necessary for the treatment starwheel to be remote from the inlet starwheel and the outlet starwheel, thereby making it necessary to provide two internal starwheels that are mounted inside the shielded enclosure so as to be tangential firstly to the treatment starwheel and secondly to the inlet or outlet starwheel respectively through the inlet or the outlet.
Although operator protection is provided very safely in such installations, they present the drawback of being very bulky because of the presence of intermediate starwheels of dimensions that have a direct influence on the length of the path to be traveled by the X-rays in order to escape from the enclosure, and thus on the ability of the enclosure to prevent radiation from escaping.